win 2k sometimes hangs

I'm dual booting Win 2k Pro and Win ME. I've solved minor niggles except this one.
I boot up the computer, select Win 2k, I get the white squares along the bottom turning to a solid white line, then the Win 2k splash screen with the red progress bar at the bottom saying starting Win 2k.
After this the screen goes blank and nothing else happens. I have to hold the reset button for 5secs to restart the computer. It can take 4 or 5 attempts to get into the Desktop. I have tried updating the display driver via Microsoft Update which says the best ( and certified) driver is already installed. I've thought about bootlogging, but can't get that far.
Motherboard is Microstar 5182.
Onboard video ATI Rage Pro 2x.
Any suggestions would be much appreciated as to how to troubleshoot this problem.
Mick the Brick.